The invention generally relates to methods of forming laminated structures, and structures formed therefrom.
Polymer films typically play an important role in a variety of applications including, but not limited to, electrical and electronic insulation applications. Some of the potential intrinsic advantages of polymers for microelectronics applications include their low cost, relative ease of handling and properties like flexibility, planarizability and stability. Depending on the needs of a particular application, the polymers usually can be modified through chemistry and engineering. Moreover, they can be processed using a variety of methods such as chemical etching, plasma etching, reactive ion etching and laser ablation.
Organic polymer films are often used in the above applications. Examples include polyimides such as KaptonNA(copyright) sold by E. I. DuPont de Nemours, Inc. of Wilmington, Del., Mylar(copyright) sold by E. I. DuPont de Nemours, Inc., polyesters, plastics, epoxies, polyethylene, polystyrene, and the like. Processing of these films requires that the polymer film can withstand elevated temperatures. For example, polyimide is a widely used insulator since it is stable to approximately 400xc2x0 C.
U.S. Pat. No. 5,525,405 the disclosure of which is incorporated herein by reference in its entirety describes a polyimide laminate and a process for preparing same, which can be bonded through a lamination step without using an adhesive. This method enables the fabrication of a polyimide laminate having a relatively large thickness of 50 microns or more. A polyimide substrate material of this type is Kapton NA(copyright). Furthermore, aqueous solutions containing sodium hydroxide or potassium hydroxide are believed to be able the wet-etch polyimide-based polymers as described in U.S. Pat. Nos. 5,350,487; 5,183,534; 4,857,143 and 4,426,253, the disclosures of which are incorporated herein by reference in their entirety. In such a way, vias and/or channel-like structures can be incorporated into a polyimide film.
Notwithstanding the above, there remains a need in the art to provide devices, such as micro-mechanical devices for example, which can be used for fluidic control on a flexible substrate. The controlled flow of fluids is of particular interest for, but not limited to, medical industrial applications, micro-mechanical and electronic applications. Therefore, it would be highly advantageous to provide methods of forming laminated structures allowing for fluidic control, along with the laminated structures themselves.
In one aspect, the invention provides a method of forming a laminate structure. The method comprises providing a first substrate and a second substrate each having first and second substrate surfaces respectively, and wherein the surfaces are present in an opposed spaced apart relationship; contacting at least one of the first or second substrate surfaces with a release material such that a portion of the first or second substrate surface is covered with the release material while the remainder of the first or second substrate surface is not covered with the release material; bringing the first and second substrate surfaces of the first and second substrates into contact with each other; and subjecting the substrates to conditions such that the portions of the first and second substrate surfaces not covered with release material become bonded to one another and a laminate structure is formed. The portion of the first or second substrate surface covered with the release material allows the first and second substrates to separate from each other such that an opening is formed therebetween that is substantially coincident with the portion covered with the release material.
In another aspect, the invention provides a laminate structure. The laminate structure comprises a first substrate having a first surface; a second substrate having an second surface opposed thereto; and a release material present on a portion of the first and second surfaces such that the remainder of the first and second surfaces not covered with release material are bonded to each other. The portion of the first and second surfaces containing release material thereon are capable of separating from each other such that an opening is formed therebetween that is substantially coincident with the portion covered with the release material.
In another aspect, the invention provides an article of manufacture comprising a laminate structure.
These and other aspects and advantages of the invention are set forth in detail herein.